The research team studied 150 participants (109 bariatric surgery patients and 41 obese control subjects) at Cornell Medical College and Weill Columbia University Medical Center, both in New York City, and the Neuropsychiatric Research Institute in Fargo, N.D.

The researchers discovered that bariatric surgery patients demonstrated improved memory and concentration 12 weeks after surgery, improving from the slightly impaired range to the normal range.

"The primary motivation for looking at surgery patients is that we know they lose a lot of weight in a short amount of time, so it was a good group to study," said John Gunstad, an associate professor in the University`s Department of Psychology.

"This is the first evidence to show that by going through this surgery, individuals might improve their memory, concentration and problem solving," he said.

The findings will be published in an upcoming issue of Surgery for Obesity and Related Diseases.